Rule-based autonomous operation is a technology for simplifying the operation and management of an information system. Rule-based autonomous control is based on a rule dictating that processing (an action), including a preset operation and management operation, is executed when a certain condition is met. A rule used in autonomous control technology is evaluated for its effect based on information, such as a result of applying the rule, and is improved in accordance with the evaluation. This method is called feedback method and is attracting attention. For instance, Japanese Patent Laid-open Publication No. 2005-354280 (hereinafter referred to as Patent Document 1) discloses a technique related to improvement through feedback of rule application history information, which contains information about a period during which a rule called a policy rule is applied, and information indicating the result of applying the rule. According to the technique, the application history information is collected and analyzed in order to collect statistical information about a condition associated with the rule, and the statistical information is used to change condition and action constitute the rule.